Heater



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HEATER Filed oct'. 9, 1939 fi g g a i i i i E i i I 10 z5 il fw il 2,5 15' 2W- f l l l Z5 lal.' M 6:5 a;

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Z M P k /z /54 "77\\` 5? Fis 6 ///\y//// E 50 X51 Inventor-s'. 55/ C. H. Wilson. 59 /Gfcwasom /w Y B9 Patented July 29, 1941 HEATER Charles H. Wilson and Grover C. Wilson,

Minneapolis,

Minn.

Application'October 9, 1939, Serial No. 298,622

(Cl. B19-38) 11 Claims.

Our invention relates to space heaters andr has for an object to provide an electricy space heater which will be extremely efficient in operation.

Another object of the invention resides in providing a` space heater which has an' exceedingly great heat exchange surface.

A still further object of the invention resides in providing a space heater which may be advan-l tageously operated at a temperature between 250 F. and 350 F.

An object of the invention resides in providing a` space heater utilizing a number of separate' units each having a separate heating element.

Another object of the invention resides in providing a space heater unit in which the heat'- ing element is completely protected.

An object of the invention residesvv in provid ing a space heater unit in which a planiform heating element of relatively thin metal is employed which is supported between two juxtaposed plates of an electrical insulating material having fairly high heat conducting properties.

A still further object of the invention resides in constructing said plates of a'silicious material such as glass or the like.

A feature of the invention resides in clamping said plates together at their edges to`ho1d the heating element in position between the plates with the surfaces of the heating element in heat exchange relation with the facing surfaces of the plates.

Another object of the invention resides in sup-` porting the units so that the air to'be heated will pass over the exposed surfaces' of the plates.

Other objects of the invention reside in the novel combination and arrangement of parts and in the details of construction hereinafter lil'-` lustrated and/or described.

In the drawing:

Fig. 1 is an elevationalV View of a space heater illustrating an embodiment of our invention.

Fig. 2 is a cross sectional view'taken on line 2-2 of Fig. 1.

f Fig. 3 is a fragmentary elevational view of one of the heating elements of the invention.

Fig. 4 is a cross sectional detail view of one of the heating units of the invention.

Fig. 5 is a wiring diagram of the invention.

portion of a building showing theinstallation of a modiiication of the invention.

The invention illustrated in Figs. l and 2 comprises a number of heating units I0, II, I2 and I3 which are all mounted'in a case I4 in a man- Fig. 6 is an elevational sectional View of a ner so that the air to be heated passes upwardly through the case and along the surfaces of the' units. Inasmuch as the heating units I 0, I I, I2 and I3 are all similar in construction, only the heating unit I3 will be described in detail, which is best shown in Figs. 1, 3 and .4.

The case I4 is constructed with a front wall I5, a rear wall I6 and end walls I1 and I8. These walls may be formed of sheet metal and are connected together in accordance with the usual practice by weldingv or soldering or by seams or in any other suitable manner. The lowermost portions of these walls are cut away as designated at I9 to form legs 2| at the corners of the case and to leave openings 20 between the legs which provide inlets for air into the case. The case I4 is provided with a top 2'3 which is connected to the walls I5, I E, I 1 and I8 by seams, welds, or otherwise.

In the uppermost portions of the walls I5 and IB are provided a number of vertical openings 22, while in the portionsA of the walls I5 and I6 below the openings 22 are provided a number of hori- The latter openings are blackeningmaterial which forms a dead black surface. These panes of glass and the various units I D, I I, I2 and I3 are supported in a manner to be presently described in detail.

The heating units I0, II, I2 and I3 are constructed of a height considerably less than the height of thel ease I4v so that, when the same are installed within the case the said units are positioned above the openings 20 and below the openings 22', thus providing a space 38 above before leaving the case.

The heating unit I3 consists of a heating ele-` ment 25 constructed from copper or from some other electrical conducting material of relatively high conductivity. vThis heating element is stamped out of a sheet of copper of a thickness betweenl one-thousandth and ve-thousandths of an inch in the form shown in Fig. 3 to provide ay number of straight runs 26 alternately connected together at their ends by curved portions By means of this construction a continuous conductor is formed of the thickness of the ma'- terial from which the heating element is constructed and of a suitable width for one-eighth and one-half ofan inch operates most advantageously. The heating element thus constructed is continuous and all of the parts thereof are integral with one another so that the problem of joining the ends of the runs is thus provided for in an exceedingly simple and practical manner.

The heating element 25 is disposed between two insulating plates 28 and 29 which are constructed of an electrical insulating material haying a fairly high conductivity for heat. A silicious material, such as glass, has been found to be suitable for the purpose. The heating e1ement 25 may be cemented to the surface of the glass plates by any suitable cement such as shellac or the said heating element may just contact the surfaces of the two plates. In either case the plates are tightly squeezed together to procure irm contact between the surfaces of the heating element and the facing surfaces of the two plates. The plates 28 and 2S are held together by means oi metal clips 3| U-shaped in form which straddle the said plates at the edges and bind the two plates securely together. Between these clips and the glass plates are provided asbestos gaskets 30 of similar form.

The various heating units I0, II, I2 and I3 are supported in the following manner. EX- tending across the lowermost portion of the case I4 and between the walls I5 and I8 thereof are two supporting bars 32 of insulating material. These bars have notches 33 in the same of a width to snugly receive the clips 3I of the heating units I5, II, l2 and I3. These supporting bars are held in position by means of bolts 34 which extend through said bars and through the walls I5, i of the case. Similar bars 35 are disposed at the portion of the case between the openings 22 and the openings 23 and extend between the walls I5 and I' and are attached in like manner by means oi bolts 31. These upper supporting bars are similarly notched, as indicated at 35, to receive the upper clips 3l of the heating elements to hold the same in position. By means of the bars 32 and 35 the various heating units are mounted in spaced relation within the case so that air may enter in between the said units, intermediate the said bars and also beyond the ends oi the same and travel past the outermost surfaces of the plates 28 and 29 of said units and be discharged into the space 3S within case I4 above the heating units. The air entering space 38 is discharged from case I4 through the openings 22 in walls I5 and I5.

The wiring diagram of the Fig. 5. The heating elements II, i2 and i3 are connected in series to a line Iii-42 by means of conductors 43, 44, 45, 46 and 1 In the conductor 43 is placed a switch 48 by means of which the current to the heaters may be interrupted. This switch is preferably disposed within space 38 of case I4 and is attached to the end wall IS of said case, as best `shown in Fig. l.

In Figs. l to 5 we have shown the invention as utilized with a portable heater. The various heating units may also be permanently installed in a building for heating the rooms within the building through air ducts and registers associated therewith. One such installation is shown in Fig. 5. In this view a portion of a building 50 has been shown which is provided with walls 5I and 52 and a floor 53 connected therewith. The various walls and floor of the building denne a room 54 which is to be heated and a basement 55 below said room. In the walls of the room 54 are arranged two registers 56 and 51 which have heater is shown in 25 of the units I0,

connected to them vertically extending ducts 58 and 59. The register 55 Serves as a warm air register and the register 51 as a cold air return register. The duct 58 is constructed similarly to the case I4 excepting that the front and rear walls thereof are formed without openings. Within this duct is arranged a number of heating units 6I, similar to the heating units I0, II, I2 and I3, which are supported on supporting bars 62 extending across the iront and rear Walls 63 and B4 of the said duct. The lowermost portions o the ducts 58 and 59 are connected together by means of another duct 65. All of the ducts 58, 59 and 65 are situated within the basement 55 and below the floor 53. In this form of the invention the heat generated by the units 6I is transferred to the air passing along the duct 58 which is discharged into the room through the register 5S. The cold air in the room is drawn through the register 51 and into the duct 59 through which the same passes along the duct 65 to the heating unit 5I where the Said air is heated and delivered to the room.

In the operation of our invention We have found that heating units constructed, as speciiied, utilizing ordinary window pane glass of double strength operates entirely satisfactory. Heating elements constructed of copper ribbon .002 of an inch in thickness and one-quarter of an inch wide produce highly desirable results when the length of the ribbon is `such that the flow of current through the ribbon maintains the heating unit at a temperature of between 250 and 350 degrees F.

Ihe advantages of our invention are manifest. Due to the use of the glass plates in the heating units, the heat exchange area of the unit is increased over and above that of the heating elcnient proper. In addition, the glass plates store heat so that when the electrical current is shut oir the units deliver heat for some time. By utilizing clips at all four edges oi the heating units, the heating elements are completely encased and protected from dust and also prevented from corroding. In this manner an extremely clean construction is provided and when the surfaces of the glass plates become soiled can be easily and quickly cleaned. With our invention heating units can be arranged in any desired manner and when supported as shown permit of maximum circulation of air past the same so that heating is rapidly and eiectively accomplished. Due to the use of the glass plates at the inner surfaces of the case the radiant heat from the heating units is absorbed and delivered to the room through the walls of the case so that all of the available heat is utilized. Heating units constructed in accordance with our invention can be used in atmospheres where fumes are present.

Changes in the specific form of our invention, as herein disclosed, may be made within the scope of what is claimed without departing from the spirit of our invention.

Having described our invention, what we claim as new and desire to protect by Letters Patent is:

We claim:

l. A space heater comprising a pair of closely positioned. glass plates, a relatively flat electric heating element disposed between said plates and in heat conducting relation therewith, said heating element having a resistance sufiicient to maintain the temperature of the heating element between 250 and 350' F., and means for supporting said plates to subject the surfaces thereof to the air to be heated.

2. A space heater comprising a pair of closely positioned glass plates, an electric heating element disposed between said plates and in heat conducting relation therewith, said heating element being constructed of a ribbon formed of copper, and means for supporting said plates to subject the surfaces thereof to the air to be heated.

3. A space heater positioned glass plates, an electric heating elesubject the surfaces thereof to the air to be heated.

ment disposed between said plates and in heat conducting relation therewith, said heating element being constructed of a ribbon formed of a metal having an electrical resistance of not over ohms per mil foot, and means for supporting said plates to subject the surfaces thereof to the air to be heated.

5. A space heater comprising a pair of closely positioned glass plates, an electric heating elethe air to be heated.

6. A space heater comprising a case having a number of spaced walls therein, glass plates positioned within said walls site the openings and tion thereto and a heating element disposed within the case between said glass plates.

8. A space heater comprising a case having a Wall extending in an up-and-down direction, a glass plate disposed within said case and extending in an up-and-down direction, said plate being spaced from said wall to provide an air therebetween, said case being proan air inlet and an air outlet communicating with said passageway, a heating element disposed in heat conducting relation to municating with said passageway, a heating element disposed in heat conducting relation to said glass plate, said wall having an opening therein opposite said glass plate through which heat is radiated from said glass plate, and a dead black coating on said glass plate.

10. A space heater means for supporting said plates to subject the surfaces thereof to the air to be heated.

11. A space heater comprising a pair of glass plates disposed adjacent one another and formed CHARLES H. WILSON. GROVER C. WILSON. 

